Topological groups

Chabauty topology

In mathematics, the Chabauty topology is a certain topological structure introduced in 1950 by Claude Chabauty, on the set of all closed subgroups of a locally compact group G. The intuitive idea may be seen in the case of the set of all lattices in a Euclidean space E. There these are only certain of the closed subgroups: others can be found by in a sense taking limiting cases or degenerating a certain sequence of lattices. One can find linear subspaces or discrete groups that are lattices in a subspace, depending on how one takes a limit. This phenomenon suggests that the set of all closed subgroups carries a useful topology. This topology can be derived from the Vietoris topology construction, a topological structure on all non-empty subsets of a space. More precisely, it is an adaptation of the Fell topology construction, which itself derives from the Vietoris topology concept. (Wikipedia).

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Topology (What is a Topology?)

What is a Topology? Here is an introduction to one of the main areas in mathematics - Topology. #topology Some of the links below are affiliate links. As an Amazon Associate I earn from qualifying purchases. If you purchase through these links, it won't cost you any additional cash, b

From playlist Topology

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What is a closed set ?

I define closed sets, an important notion in topology and analysis. It is defined in terms of limit points, and has a priori nothing to do with open sets. Yet I show the important result that a set is closed if and only if its complement is open. More topology videos can be found on my pla

From playlist Topology

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Topology 1.5 : Order Topology

In this video, I introduce the order topology and prove that it is Hausdorff. Email : fematikaqna@gmail.com Code : https://github.com/Fematika/Animations Notes : None yet

From playlist Topology

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Topology 1.7 : More Examples of Topologies

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From playlist Topology

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Connectedness

In this video, I define connectedness, which is a very important concept in topology and math in general. Essentially, it means that your space only consists of one piece, whereas disconnected spaces have two or more pieces. I also define the related notion of path-connectedness. Topology

From playlist Topology

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David Corwin, Kim's conjecture and effective Faltings

VaNTAGe seminar, on Nov 24, 2020 License: CC-BY-NC-SA.

From playlist ICERM/AGNTC workshop updates

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Topology 1.1 : Open Sets of Reals

In this video, I give a definition of the open sets on the real numbers. Email : fematikaqna@gmail.com Code : https://github.com/Fematika/Animations Notes : None yet

From playlist Topology

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Topology 1.3 : Basis for a Topology

In this video, I define what a basis for a topology is. Email : fematikaqna@gmail.com Code : https://github.com/Fematika/Animations Notes : None yet

From playlist Topology

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Rational points and fundamental groups. - Ellenberg - Workshop 2 - CEB T2 2019

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From playlist 2019 - T2 - Reinventing rational points

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Nicolás Matte Bon: Confined subgroups and high transitivity

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From playlist Dynamical Systems and Ordinary Differential Equations

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Jean-Louis Koszul - Interview à l'occasion des 50 ans du bâtiment de l'Institut Fourier

Jean-louis Koszul accompagné de Jacques Gasqui Aux questions : Ariane Rolland (CNRS) et Romain Vanel (CNRS) A l'image : Fanny Bastien (CNRS)

From playlist 50 ans du bâtiment Institut Fourier

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Topology 1.4 : Product Topology Introduction

In this video, I define the product topology, and introduce the general cartesian product. Email : fematikaqna@gmail.com Code : https://github.com/Fematika/Animations Notes : None yet

From playlist Topology

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The Chabauty Topology 2 (Lecture-1) by Ian Biringer

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From playlist Probabilistic Methods in Negative Curvature (Online)

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Nicholas Triantafillou, Computing isolated points on modular curves

VaNTAGe seminar, on Nov 10, 2020 License: CC-BY-NC-SA.

From playlist ICERM/AGNTC workshop updates

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Topologist Sine Curve

Here is one of the most important curves in mathematics. It is an example of a set that is connected, but not path-connected, and is very prominent in topology and analysis. Topology Playlist: https://www.youtube.com/playlist?list=PLJb1qAQIrmmA13vj9xkHGGBXRMV32EKVI Subscribe to my channel

From playlist Topology

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Gluing a Torus

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From playlist Algebraic Topology

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Ishai Dan Cohen:The polylog quotient and the Goncharov quotient in computational Chabauty-Kim theory

Abstract: Polylogarithms are those multiple polylogarithms which factor through a certain quotient of the de Rham fundamental group of the thrice punctured line known as the polylogarithmic quotient. In joint work with David Corwin, building on work that was partially joint with Stefan We

From playlist HIM Lectures: Trimester Program "Periods in Number Theory, Algebraic Geometry and Physics"

Related pages

Mathematics | Degeneracy (mathematics) | Lattice (group) | Euclidean space | Limiting case (mathematics) | Locally compact group